Ariel Owners Motorcycle Club

Should the timing chain be this loose?

You can see the grooves at the bottom where the chain has been rubbing against the case, I’ve seen many bikes with these grooves so might be normal .
Was thinking of cutting a piece of Teflon maybe and somehow sticking it to the bottom of the case to minimize noise,has anyone ever done something like this?
The p/o had fitted some thick pipe around the two mounting tabs but doesn’t seem to do anything.

Any advice would be greatly appreciated .

Thanks

You loosen the three bolts holding the magdyno to its platform and move it backwards to tension the chain. Be very careful putting the oil pump back - that gasket seems to have a will of its own and a proclivity for jumping out of place!

simon didn't explicitly say it .... your chain is too loose: it's not normal and it needs to be tightened.

As Simon ssays, you need to slacken the three bolts that hold the magneto to it's platform and move it back. You may need the foor rest and foot rest spacer off to give you enough space to work under there ...

Yes, way too loose. Nicholson states: "When slack midway between sprockets at the tightest point exceeds 1/2 inch, adjust to 1/4 inch."

I thought it was 1/4" - but my '55 Onwers Guide clearly gives 3/8"...whatever, yours is way way too slack!
Make sure the sprockets are in line and the mag is close enough against the back of the timing cover (if there's a rubber seal between mag and cover it might need some pressure to keep it in place while the bolts are tightened).

SG

Thank you all for the helpful information, will move the Mag back and tension the chain to between 3/8 - 1/4”.

I’m still learning on this bike, trying to get it back on the road after it being sat for years. I have a new Morgo plunger pump to replace the old one as it had a chewed tread.

Tthe magneto drive shaft is weak and may be running out of true if there's ever been a mishap with the chain or the sprocket levered off. Genuine puller or good copy is a must. The lower face of the platform can wear near the oval holes and want to return to the most used position. The only cure for that is to remove the plate and weld the worn areas and make the surface flat as it originally was. The chain should be just off tight . Just a noticeable slack and no more or it will give the maggy hell as I imagine your chain is doing. Replace the chain if worn. It's only "good" bike chain and usually lasts well. Check it has no high and low spots indicating sprocket run out. Exercise care in tightening the maggy nut. You can't easily stop it turning if the thread is damaged or washer missing. holding by the points assembly is not recommended. Nev

Dont tension the chain in the loosest spot...........and always turn the chain over a few revolutions after tensioning to make sure it doesnt come up dead tight.......Same goes for primary chain........always make sure its not dead tight somewhere as it turns.